Degassing tube and ejection cone for a turbine engine, as well as tool for assembly thereof

Abstract

An aircraft turbine engine module, including a degassing tube and an ejection cone. The tube and the cone are engageable together by structures which cause them to be centered when engaged together. Also provided is a locating and adjusting tool for assembling the module.

The invention claimed is: 
     
       1. Locating and adjusting tool for the assembly of a unit of a turbine engine of an aircraft, the unit comprising a degassing tube and an ejection cone,
 the degassing tube having an extended form and comprising first fixing means configured to fix to a first element of the turbine engine at a first longitudinal end, the degassing tube also comprising first centering means which are located at an external periphery of the degassing tube and at a distance from said first longitudinal end, said first centering means being configured to co-operate with second centering means of the ejection cone which is designed to be traversed by said degassing tube, said first centering means having a polygonal cross-sectional profile and being formed by external flat surfaces of the degassing tube that extend annularly around an outside of the degassing tube, 
 the ejection cone having an extended form and comprising second fixing means configured to fix to a second element of the turbine engine at a second longitudinal end, the ejection cone also comprising the second centering means which are located at an inner periphery of the ejection cone and at a distance from said second longitudinal end, said second centering means being configured to co-operate with said first centering means of the degassing tube which is designed to traverse said ejection cone, the ejection cone comprising at least one annular stiffener at the inner periphery, said second centering means being fixed in a detachable manner to said at least one annular stiffener, said second centering means comprising an annular row of tabs configured to be supported radially on said first centering means, 
 wherein the locating and adjusting tool comprises:
 a first ring configured to be applied and fixed to said second element of the turbine engine and to also be, in a sequence manner, applied and fixed to the second longitudinal end of larger diameter of said ejection cone, said first ring being configured to be traversed by said degassing tube, 
 a second ring configured to be traversed by said degassing tube and to be accommodated in said ejection cone, 
 ring connecting struts, which extend between the first and second rings and are fixed to the first and second rings, these ring connecting struts being configured to be accommodated in said ejection cone, and 
 a third ring configured to be traversed by said degassing tube and to carry, in a detachable and sequenced manner, a tubular finger of the locating and adjusting tool, said tubular finger comprising third centering means substantially identical to said first centering means of said degassing tube, said third centering means having a polygonal cross-sectional profile and being formed by external flat surfaces of the tubular finger that extend annularly around an outside of the tubular finger, said third ring being directly fixed on said second ring by fourth means allowing an adjustment of a radial misalignment of axes of said second and third rings, said fourth means comprising an annular row of first screws, the first screws being carried by the third ring. 
 
 
     
     
       2. Tool according to the  claim 1 , wherein said third ring comprises an inner cylindrical centering surface which is configured to co-operate with an external cylindrical surface of said tubular finger and, in a sequenced manner, with an external cylindrical surface of a tubular casing of the locating and adjusting tool, said tubular casing comprising an inner surface of polygonal form in cross section, which is complementary to that of said first centering means of said degassing tube. 
     
     
       3. Tool according to  claim 2 , wherein the tubular casing is sectioned and comprises several sectors. 
     
     
       4. Tool according to  claim 2 , wherein the inner surface of the tubular casing is hexagonal form in cross section. 
     
     
       5. Assembly method of a unit of a turbine engine of an aircraft, by means of a locating and adjusting tool according to  claim 2 , the unit comprising a degassing tube and an ejection cone,
 the degassing tube having an extended form and comprising first fixing means configured to fix to a first element of the turbine engine at a first longitudinal end, the degassing tube also comprising first centering means which are located at an external periphery of the degassing tube and at a distance from said first longitudinal end, said first centering means being configured to co-operate with second centering means of the ejection cone which is designed to be traversed by said degassing tube, said first centering means having a polygonal cross-sectional profile and being formed by external flat surfaces of the degassing tube that extend annularly around an outside of the degassing tube, 
 the ejection cone having an extended form and comprising second fixing means configured to fix to a second element of the turbine engine at a second longitudinal end, the ejection cone also comprising the second centering means which are located at an inner periphery of the ejection cone and at a distance from said second longitudinal end, said second centering means being configured to co-operate with said first centering means of the degassing tube which is designed to traverse said ejection cone, the ejection cone comprising at least one annular stiffener at the inner periphery, said second centering means being fixed in a detachable manner to said at least one annular stiffener, said second centering means comprising an annular row of tabs configured to be supported radially on said first centering means, 
 wherein the assembly method includes the steps of:
 a) fixing said degassing tube to the first element of the turbine engine and fixing said first ring of said locating and adjusting tool to the second element of the turbine engine, so that said second and third rings are traversed by said degassing tube, said fourth means between said second and third rings not being tightened, 
 b) mounting said tubular casing around said degassing tube and inside said third ring, said fourth means between said second and third rings not being tightened, 
 c) detaching said locating and adjusting tool from said second element of the turbine engine, fixing said tubular finger to said third ring, and inserting said locating and adjusting tool in said ejection cone, so that said tubular finger co-operates with said second centering means, which are freely mounted in a radial direction with regard to said ejection cone, then fixing said first ring to said ejection cone, 
 d) rigidly fixing said second centering means with regard to said ejection cone, and 
 e) mounting said ejection cone around said degassing tube, so that said first and second centering means co-operate together, then fixing said ejection cone to said second element of the turbine engine. 
 
 
     
     
       6. A set comprising a locating and adjusting tool according to  claim 1  and a unit of a turbine engine of an aircraft, the unit comprising a degassing tube and an ejection cone,
 the degassing tube having an extended form and comprising first fixing means to a first element of the turbine engine at a first longitudinal end, the degassing tube also comprising at an external periphery of the degassing tube and at a distance from said first longitudinal end first centering means configured to co-operate with second centering means of the ejection cone which is designed to be traversed by said degassing tube, said first centering means having a polygonal cross-sectional profile and being formed by external flat surfaces of the degassing tube that extend annularly around an outside of the degassing tube, 
 the ejection cone having an extended form and comprising second fixing means to a second element of the turbine engine at a second longitudinal end, the ejection cone also comprising the second centering means which are located at an inner periphery of the ejection cone and at a distance from said second longitudinal end, said second centering means being configured to co- operate with said first centering means of the degassing tube which is designed to traverse said ejection cone, the ejection cone comprising at least one annular stiffener at the inner periphery, said second centering means being fixed in a detachable manner to said at least one annular stiffener, said second centering means comprising an annular row of tabs configured to be supported radially on said first centering means. 
 
     
     
       7. Tool according to  claim 1 , wherein each of said first screws passes through a corresponding hole of the second ring, each of said first screws having a respective diameter which is smaller than a diameter of the corresponding hole, so that the third ring is able to be moved in a radial plane relative to the second ring when said first screws are not tightened. 
     
     
       8. Tool according to  claim 1 , wherein each ring connecting strut is fixed to the first ring and to a first annular face of the second ring, the third ring being directly fixed on a second annular face of the second ring by said fourth means, the second annular face of the second ring being opposite to the first annular face of the second ring. 
     
     
       9. Tool according to  claim 1 , wherein each ring connecting strut is fixed to the first ring and to a first annular face of the second ring, the third ring comprising a collar, the collar of the third ring being directly fixed on a second annular face of the second ring by said fourth means, the second annular face of the second ring being opposite to the first annular face of the second ring. 
     
     
       10. Tool according to  claim 1 , wherein said tubular finger is fixed to the third ring by an annular row of second screws when the tubular finger is carried by the third ring. 
     
     
       11. Tool according to  claim 1 , wherein said third ring comprises an unthreaded inner cylindrical centering surface which is configured to co-operate with an unthreaded external cylindrical surface of said tubular finger and, in a sequenced manner, with an unthreaded external cylindrical surface of a tubular casing of the locating and adjusting tool, said tubular casing comprising an inner surface of polygonal form in cross section, which is complementary to that of said first centering means of said degassing tube.